Pylons
The original design had pylons spaced every 100ft.
I would propose spacing at least 200-300ft to both minimize pylon costs since they account for about 50% of the total costs and to speed construction.
Also, I propose making sure the pylons can support the weight of additional tubes. I envision a system where multiple tubes could be stacked on top of one another (see thoughts on Tube construction). This could allow pylons to service multiple routes, or double up an existing route.
The tubes would be arranged in a 2x2 or 2x3, etc configuration with 2 tubes wide (there and back) and could go as high as possible depending on what the pylons can support. Since each tube is capable of supporting it's own weight, stacking the tubes will not put extra weight or stress on the tubes at the bottom.
These extra tubes could be added after the original construction is complete.
#########Witnaaay - Mounting a third tube would be a good idea, so that we could take one down for maintenance without shutting down the entire hyperloop system. On hot days the entire tube system would expand, so we should consider a 'soft' dock, between tubes and also perhaps between tubes and pylon. Similarly, a steel/iron pipe would get very warm on a hot day so we would want to shade it.
In event of an emergency we need to be able to evacuate the tube quickly. Every few tubes we would want an emergency exit and a scaffolding to allow quick egress.
#########Pranav Jain - Another idea I had about the pylons is that since we cannot have the actual tube go up and down every single hill/mountain or other object in the way, we could keep the pylons at a fixed height above sea level. This would mean that even if the roads and mountains are changing elevation, we modify the pylon height so that it the tube will be at a level height.Some problems with this idea is that it might cause some problems when the elevation is to rapid and might cause some outrageously tall pylons. This might work for a hilly area, but if we need to deal with a really big mountain, then I would recommend slowly changing the tubes height (relative to sea level) slowly over hundreds of miles. These are just my ideas on how to solve some problems that I saw when designing the route for Hyperloop from LA to SF.
I also thought maybe we could just have a poured concrete base for the pylon that provides a secure foundation and then install a steel truss system above it that connects to the tubes? The steel truss could be prefab'd offsite and just attached to the concrete base. Would that create a secure enough system? Would that be cheaper/better/etc than a steel reinforced poured concrete entire pylon? Would it be faster to install? I think it would meet most of the requirements, just not sure of the stability.
Thoughts?